Bioengineering Graduate Program - MPhil Thesis Presentation - Double Emulsified Generation of Liposome for Gene Delivery

Liposome that extensively applied in drug and gene delivery has shown its outstanding capability of delivery efficiency and flexibility of modification. The natural properties of the amphiphilic lipids enable them the advantage for transfection. Yet the formation of liposomes using traditional methods has its intrinsic disadvantage such as batch-to-batch instability and low encapsulation rate. The modern synthesis methods with droplet-based microfluidics bring new possibilities to the synthesis of liposomes.

In this thesis, we employed glass capillary microfluidics that can be simply integrated on a glass slide. While the manufacture of the capillaries avoided complicated etching and lithography as the requirements of silica or PDMS chip. The double emulsion of w/o/w droplets was produced in the capillary microfluidics with the combination of co-flowing and flow-focusing configuration. We proved the stable formation of the double emulsion with high throughput, while the flowing regime can be precisely controlled by adjusting the flowrate of each phase. The w/o/w droplets generated by double emulsion in capillary microfluidic chip can be an ideal precursor of liposome. Extrusion and PEGylation are used to scale down and stabilize the liposome. We encapsulated the DNA-peptide complex so called nano-berry as the cargo to be delivered and analyzed the internalization and gene expression between the free nano-berries and that encapsulated in the liposome. The result showed with the present of liposome, both the internalization and expression level is elevated. Which provided a simple way to produce a reliable gene delivery system